A dream team of Rob Flain & Paul McConville (the world’s most experienced QUAD service engineers), Jan Ertner (30 years of experience in QUAD design), Peter Comeau (the acoustic director behind some of QUAD’s most successful loudspeakers) and David McNeill (the industrial designer responsible for two decades of QUAD innovations) were all a part of this labour of love, making no compromise in the demand for a product that could bear the name of Quad 33 Preamplifier and Quad 303 Power Amplifier.

The QUAD 303 power amplifier was intended for normal domestic use with loudspeakers of moderate efficiency, but was also used by broadcasting and recording studios, worldwide, who appreciate its excellent performance and dependability. The ethos hasn’t deviated. The outstanding performance of the QUAD 303 is still celebrated to this day, and is largely due to the unique output circuit developed by QUAD.

In reissuing the QUAD 303 power amplifier concept, exactly like the matching 33 preamplifer, QUAD’s incomparably experienced service team was matched with the equally adept engineering team to reinvoke the design, romance and performance in a thoroughly modern iteration of a hi-fi legend. As with the new QUAD 33, every aspect of design and performance has been analysed and re-engineered way beyond simply modernising components and refreshing of specifications.

Much like the original, the new QUAD 303 maintains its faithfulness to the original by employing the famous QUAD Symmetrical Triples, employed to provide a completely symmetrical output stage, greatly reducing distortion and rendering the resting current independent of output transistor temperature.This development enables the designers to reduce distortion to emphatically low levels without sacrificing stability and to maintain this excellence under all dynamic conditions. To put this in perspective, the lowest theoretical distortion present on the very source material will still be some hundred times greater than that the QUAD 303.

The industrial design of the new QUAD 303 is instantly recognisable and is true QUAD. The anodised chassis CNC-routed heat sinks on either side offer enduring quality which the tank housing also provides a rugged structure that resists interference from external vibrations.

Technical Specifications

Model: QUAD 303
Description: Power Amplifier
Inputs: 1 x Line, 1 x XLR
Outputs: 1 x 12 V Trigger, 1 x Stereo Speaker, 1 x 12 V Trigger (Link)
Gain: +29 dB
Rated Power Output:
Stereo: 2 x 50 W (8 ohms, THD <1 %)
Stereo: 2 x 70 W (4 ohms, THD <1 %)
Bridged: 140 W (8 ohms, THD <1 %)
Bridged: 170 W (4 ohms, THD <1 %)
Frequency Response: 20 Hz – 20 kHz (+/-0.3 dB)
Total Harmonic Distortion (THD): <0.002 % (1 kHz)
Input Impedance: 10 kOhms
Input Sensitivity: 700 mVrms (Line), 1.5 Vrms (XLR)
Signal-to-Noise Ratio (S/N): >108 dB (A – weighted)
Max. Output Current: 10 A
Standby Power Consumption: <0.5 W
Net Weight: 8.4 kg
Dimensions (W x H x D): 120 x 176 x 325 mm
Finish: Classic QUAD Grey
Power Requirements: 220 – 240 V – 50 / 60 Hz, 100 – 120 V – 50 / 60 Hz